Procedures for visa processing with NOC

Kindly assist with the following visa procedures.

What are the documentation procedures for applying a visa for an employee who is currently working in Qatar under a different sponsor. Note that he will be given an NOC by his present employer but advised to leave the country and come back.

Need to know what the documents needed to be submitted when applying for new visa for this person? Do we only need NOC from his currently employer or any other documents required? (i.e. Like copy of Company Registration etc..

Appreciate if some one list-out the procedures/documentation requirements etc. for applying a visa with NOC provided by the current employer.

Thanks in advance.